/*
 * Copyright 2021 The Android Open Source Project
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package androidx.navigation.testing

import androidx.navigation.NavBackStackEntry
import androidx.navigation.NavDestination
import androidx.navigation.NavigatorState
import androidx.savedstate.SavedState

/**
 * An implementation of [NavigatorState] that allows testing a
 * [androidx.navigation.Navigator] in isolation (i.e., without requiring a
 * [androidx.navigation.NavController]).
 */
public expect class TestNavigatorState() : NavigatorState {
    public override fun createBackStackEntry(
        destination: NavDestination,
        arguments: SavedState?
    ): NavBackStackEntry

    /**
     * Restore a previously saved [NavBackStackEntry]. You must have previously called
     * [pop] with [previouslySavedEntry] and `true`.
     */
    public fun restoreBackStackEntry(previouslySavedEntry: NavBackStackEntry): NavBackStackEntry
}
